What I meant by underrated is that I feel Michael Keaton's Batman should be numero uno, and you have that right to choose whomever as your #1 guy. Bale's has significant alterations from the source material. They both have alterations from the source material. Which has more alterations from the source material?
Young Bale Bruce's parents took him to see an opera called Mefistofele.
Bale Bruce's father was mugged by a presumably homeless Joe Chill in a mugging turned panicked double murder. Chill was quickly caught by the police and arrested.
Bale's Bruce tried to murder Joe Chill but Carmine Falcone has Chill assassinated, for testifying against cellmate Falcone.
Bale's Bruce was trained by Ra's al Ghul.
Bale's Bruce was given his Nomex survival suit, utility harness, grapple gun, memory cloth cape, the Tumbler, Batpod, The Bat etc. by Lucius Fox - the head of environmental procedures, defense projects, consumer products - all prototypes in the Applied Sciences Division and Fox is the CEO of Wayne Enterprises.
Alfred comes up with the idea of ordering parts of the cowls from Singapore, via a dummy corporation and then separately place an order to a Chinese company for the ears for the cowl. Cain's Alfred says they'll have to be large orders, to avoid suspicion. 10,000. Bale's Bruce looks shocked and dumbfounded and says "Well, at least we'll have sparse." Cain's Alfred figures out that there is a problem with the graphite in the mask. The next 10,000 will be up to specifications.
Alfred saves Bale's Bruce while he's hallucinating from Scarecrow's fear toxin.
Scarecrow is an Arkham Asylum psychiatrist with a potato sack on his head, not a collage professor of psychology. The fear toxin is made by Ra's al Ghul, not by Scarecrow.
Ra's al Ghul burns down Wayne Manor.
Alfred saves Bale's Bruce from the fire in Wayne Manor.
Lucius Fox saves Gotham City by synthesizing an antidote to the fear toxin.
Lucius Fox also saves Gotham City by figuring out about the microwave emitter scheme.
Rachel Dawes defeats Scarecrow with her taser.
Joker is a bomber wearing clown makeup. Bombed a hospital, bombed a city jail, bombed a judge's car, bombed a warehouse, tried to bomb two ferryboats.
Joker creates Two-Face.
Half of Two-Face's face is burned off by fire, not acid scarred.
Bale's Batman frames himself for the murders Two-Face committed and retires for 8 years to preserve a false image of Harvey Dent as an incorruptible heroic District Attorney.
Bane makes Bale's Bruce bankrupt.
Selina the Cat is a hacker spy hired by Bane.
Talia stabs Bale's Batman and tries to detonate a bomb.
Bale's Bruce happily re-retires in Italy with Selina once he’s found a replacement. No oath to avenge his parents by spending the rest of his life warring on crime.
Robin John Blake becomes the replacement Batman.
Young Michael Keaton Bruce's parents took him to see a movie called Footlight Frenzy.
Keaton Bruce's mother was mugged by Joe Chill and the Waynes were murdered by Jack Napier. [In Comics Interview #77 (1990) DC writer Jack C. Harris asked Batman (1989) producer Michael Uslan, "Was the other man in the alley on the night the Wayne's murder suppose to be Joe Chill?" Michael Uslan explained, "Yes. In fact you'll recall that it was Chill who grabbed Bruce's mother's necklace." Harris asked Uslan, "Did you agree with the change to Sam Hamm's script by Warren Skarren to make the Joker the murderer of Bruce Wayne's parents?" Michael Uslan explained, "Yes. In fact, and you'll have to check this with Bob Kane, I think he [Bob Kane] said that if the Joker had been created earlier [in 1939], he would have been the Wayne's killer in the comics, as well."]
Keaton's Bruce was presumably trained by Chinese martial artist Chu Chin Li, Tsunetomo and French Detective Henri Ducard, according to Batman (1989) screenwriter Sam Hamm's Blind Justice (1989).
Keaton's Bruce presumably secretly invented his Batsuit, utility belt, grapple gun, etc., the Batmobile [Batmissile], Batwing and Batskiboat as top secret experimental designs at the Wayne Technologies extension of the Wayne Enterprises Corporation. [In Comics Scene #9 (1989) Michael Keaton explained, "The coolest thing about Batman to me was that he wasn't your typical superhero. He has no superpowers and basically has to rely on his intelligence to create things that will protect him." The official Warner Books Batman Returns novelization by Craig Shaw Gardner explains that Max Shreck payed to get the blueprints of the Batmobile "from a disgruntled former employee of the car's designer. The Penguin let the businessman handle that sort of particular." And in Batman Returns we see Keaton's Bruce repairing the Batmobile himself in the cave.]
Keaton's Bruce is a member of Gotham City's Democrats club.
As the mysterious vigilante Batman, he's terrifying superstitious criminals into believing that he is a supernatural giant bat that drinks blood and can't be killed.
Keaton's Bruce had a relationship with photographer Vicki Vale.
The hood Jack Napier was robbing Axis Chemicals and he found himself cornered by Batman on one of the factory's catwalks, and he fell into the vat of chemicals that turned his skin chalk-white, his hair green -- with a perpetual freakish grin -- he named himself -- the Joker! Then he resumed his criminal career under that name.
[Batman (1989) scriptwriter Sam Hamm explained in Amazing Heroes #159 (1989), "The origin sequence is very similar to what is seen in the comic books. He and his gang are surprised by the police at a staged robbery at Axis Chemicals - which was changed from Ace Chemicals for legal reasons - and Batman intervenes. The thug who will become the Joker is dumped into a vat. He emerges in his full horrific glory. Jack Napier is not a nod to Jack Nicholson [nor a tribute to Alan Napier]. It's actually a play on the word jackanapes, in the same vein that the Riddler's name was E. Nigma [a play on the word enigma]." In the book Jack's Life: A Biography by Patrick McGilligan, it's explained, "Talking with Bob Kane, Nicholson learned that Kane had based the Joker on a character played by Conrad Veidt in a 1928 movie, The Man Who Laughs. The Veidt character wears a perpetual freakish grin because as a boy his check muscles were slit. Nicholson made an effort to track down the silent picture, directed by the German Expressionist Paul Leni, and watched it for pointers."]
The Joker murders with a grisly venom he calls Smylex, which, as it snuffed the life out of each gasping victim, contracted the muscles of the doomed man's face into a ghastly grin, the sign of death from the Joker! The Joker feels that is turning murder into art.
Ironically, he uses 'jokes' as deadly weapons -- for example, a hand buzzer that electrocutes, a phony flower that squirts acid.
The Joker vandalizes art [like Cesar Romero's Joker].
Batman gave Vale his manila envelope with 50 sheets of paper to take to the Gotham Globe, full of chemical equations and lists of woman's beauty products and hygiene products that the Joker had poisoned with Smylex, and that the poison works when the products are worn together. The Gotham Globe reports, "Batman Cracks Joker's Poison Code!"
Keaton's Batman saves Gotham City from the Joker.
Keaton's Bruce has a relationship with Selina Kyle and Keaton's Batman fights Catwoman.
Keaton's Bruce figured out that the Penguin already knew who his parents were, and was at the Hall of Records to make a list of the names of children to kidnap and murder. While researching old Gotham Globe newspapers Keaton's Bruce discovered that numerous reports of missing children in several towns was the reason police closed down the Red Triangle Circus's fair-grounds, folded the tents. However, one performer vanished before he could be questioned. Keaton's Bruce deduced that the Arctic World pavilion was Penguin's hideout now.
The Penguin rarely appears in public without at least one of his trick umbrellas, including umbrellas which fire bullets, sword-handled umbrellas, a flamethrower umbrella, and a helicopter umbrella. [In the book Batman Returns: The Official Movie Book (1992) by Michael Singer, Tim Burton explained, "I feel like a real kindred spirit with Danny [DeVito], and I think we're really creating something that people will see and enjoy as a natural expansion of the comic book character."]
The Penguin runs for mayor [like Burgess Meredith's Penguin].
Keaton's Batman quickly figures out that the Penguin is now using penguins he can control by headgear, using a pitch and frequency that would cause penguins to follow his every command, like zombies to the Penguin's radio signal controls, with rockets on their backs. Batman's Batskiboat homed in on the coordinates, Alfred at a console in the Batcave jammed the frequency and turn them around to return to the Arctic World.
Keaton's Batman, with a little help from Alfred, saved Gotham City from the Penguin.